Line transition having a notch in the dielectric substrate adjacent the coupling line pattern

Abstract

The present invention provides a line transition and a method for manufacturing the same. The line transition is constructed such that a planar circuit can be arranged in the direction parallel to the propagation direction of electromagnetic waves propagating through a solid waveguide, the coupling characteristics of the solid waveguide with the planar circuit formed on a dielectric substrate are not influenced by the assembly precision of the waveguide and the circuit, and the line transition characteristics are not affected by a variation in manufacturing the dielectric substrate. Notches are formed at the edges of the dielectric substrate in the vicinities of coupled-line pattern segments formed on a dielectric substrate. The notches are formed by punching through holes in a ceramic green sheet serving as a motherboard, firing the motherboard, and cutting the motherboard using dicing lines passing through the through holes.

1. A line transition comprising:
 a dielectric substrate; 
 a waveguide, the waveguide propagating electromagnetic waves within a three-dimensional space; and 
 a conductive pattern disposed on the dielectric substrate, the conductive pattern including a coupled-line pattern segment electromagnetically coupled with the electromagnetic waves propagating through the waveguide and a transmission-line pattern segment extending from the coupled-line pattern segment, wherein 
 the dielectric substrate is disposed parallel to an E plane of the waveguide, and 
 an edge of the dielectric substrate has a notch in the vicinity of the coupled-line pattern segment, the notch having a side that is parallel to a signal propagation direction of the coupled-line pattern segment, the length of the side being equal to or longer than a width of the E plane of the waveguide, and the notch does not extend to ends of the edge of the dielectric substrate in which the notch is located. 
 
   
   
     2. A high frequency module including the line transition according to  claim 1 . 
   
   
     3. The line transition according to  claim 1 , wherein the dielectric substrate is disposed in substantially a middle of the waveguide. 
   
   
     4. The line transition according to  claim 1 , wherein the waveguide is a solid waveguide. 
   
   
     5. The line transition according to  claim 1 , wherein the conductive pattern is a planar circuit which accomplishes planar-circuit to waveguide transition.